Title :
What´s that deal with the DCT?
Author_Institution :
California Inst. of Technol., Pasadena, CA, USA
fDate :
7/1/1993 12:00:00 AM
Abstract :
Discrete cosine transforms (DCTs) and discrete Fourier transforms (DFTs) are reviewed in order to determine why DCTs are more popular for image compression than the easier-to-compute DFTs. DCT-based image compression takes advantage of the fact that most images do not have much energy in the high-frequency coefficients. It is suggested that DCTs are more popular because fewer DCT coefficients than DFT coefficients are needed to get a good approximation to a typical signal, since the higher-frequency coefficients are small in magnitude and can be more crudely quantized than the low-frequency coefficients.<>
Keywords :
Fourier transforms; data compression; discrete cosine transforms; image processing; DCT-based image compression; discrete Fourier transforms; discrete cosine transforms; higher-frequency coefficients; Data compression; Fourier transforms; Image processing; discrete cosine transforms;
Journal_Title :
Computer Graphics and Applications, IEEE